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arXiv · 1504.04507

An efficient probe of the cosmological CPT violation

Gong-Bo Zhao·Yuting Wang·Jun-Qing Xia·Mingzhe Li·Xinmin Zhang
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Abstract

We develop an efficient method based on the linear regression algorithm to probe the cosmological CPT violation using the CMB polarisation data. We validate this method using simulated CMB data and apply it to recent CMB observations. We find that a combined data sample of BICEP1 and BOOMERanG 2003 favours a nonzero isotropic rotation angle at $2.3σ$ confidence level, ie, $Δα=-3.3 \pm1.4$ deg (68% CL) with systematics included.

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Gong-Bo Zhao, Yuting Wang, Jun-Qing Xia, Mingzhe Li, Xinmin Zhang. 2015-07-21. An efficient probe of the cosmological CPT violation. https://doi.org/10.1088/1475-7516%2F2015%2F07%2F032

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